Compare Elements

Compare two chemical elements side by side across 19 atomic and physical properties.

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Element comparison
Property Ac Actinium Pr Praseodymium
Atomic Number 89 higher 59 higher
Symbol Ac different Pr different
Name Actinium different Praseodymium different
Atomic Mass 227.0277 higher 140.9077 higher
Category Actinides different Lanthanides different
Period 7 higher 6 higher
Group 3 same value 3 same value
Block f-Block same value f-Block same value
Standard State Solid same value Solid same value
Electronegativity 1.1 lower 1.13 lower
Atomic Radius 260 higher 239 higher
Ionization Energy 5.17 lower 5.464 lower
Electron Affinity — no data — no data
Oxidation States +3 same value +3 same value
Melting Point 1324 K (1050.85 °C) higher 1204 K (930.85 °C) higher
Boiling Point 3471 K (3197.85 °C) lower 3793 K (3519.85 °C) lower
Density 10.07 higher 6.77 higher
Electron Configuration [Rn]7s2 6d1 different [Xe]6s2 4f3 different
Year Discovered 1899 different 1885 different

higher lower